Mobile authentication is an essential service to ensure the security of engaging parties in a ubiquitous wireless network environment. Several solutions have been proposed mainly based on both centralised and distributed authentication models to allow ubiquitous mobile access authentication; however, limitations still exist in these approaches, namely flexibility, security and performance issues and vulnerabilities. These shortcomings are influenced by the resource limitations of both wireless networks and the mobile devices together with inter-technology and inter-provider challenges. In this paper, the authors reviewed the major techniques in the field of ubiquitous mobile access authentication, which has attracted many researchers in the past decade. After investigating existing mobile authentication models and approaches, the common challenges are summarised to serve as the solution key requirements. The identified key solution requirements allow analysing and evaluating mobile authentication approaches.
